A wireless network may include a plurality of basic service sets (BSS). A carrier sense multiple access with collision avoidance (CSMA/CA) mechanism in an 802.11 standard is usually used to ensure that access points (AP) and stations (STA) in different BSSs can access a wireless medium, and no conflict occurs between all nodes.
However, when a physical protocol data unit (PPDU) is transmitted on a border between two BSSs based on the CSMA/CA mechanism, usually APs/STAs in only one cell can transmit data, but APs/STAs in another cell cannot transmit data. Consequently, resources cannot be fully used.
In this case, a spatial-reuse parallel transmission concept is proposed in a new 802.11ax standard. For example, as shown in FIG. 1, when a PPDU is transmitted between an AP 1 and a STA 1 on a link 1 in a BBS 1, an AP 2 in a BSS 2 may determine, based on an obtained spatial reuse parameter such as Transmission Power Control (TPC) information, whether data transmission on a link 2 established between the AP 2 and a STA 2 in the BSS 2 causes interference to the link 1 between the AP 1 and the STA 1. If the AP 2 determines that the data transmission causes no interference to the link 1, the AP 2 may continue to transmit data after the PPDU transmission between the AP 1 and the STA 1 ends. To be specific, the AP 2 may transmit data across a boundary of the PPDU.
However, after the PPDU transmission between the AP 1 and the STA 1 ends, the AP 1 may further interact with another AP/STA. For example, when the AP 1 subsequently establishes a link 3 to interact with a STA 3 in an overlapped basic service set (OBSS), the link 2 between the AP 2 and the STA 2 causes interference to data transmission on the link 3.